is this just her age i wonder or is she just a bad dog, don't get me wrong i am so attached to her now that the very thought of parting with her breaks my heart any advise would be appreciated.
Neither... It's not just her age, as this behaviour isn't normal for a dog of any age. But she's not a "bad dog" - she's obviously very troubled and expressing this through her behaviour.
What did the behaviourist suggest you did, other than putting her on tablets? Generally medication should be used to enable behaviour modification to take place, not as the single solution...
Has she been checked by the vet for any physical problem? If the vet is happy, it may be worth getting a chiropractor or physiotherapist to look at her too (our dog became very temperamental with other dogs, and it turned out she has a bad back, which we now manage with 6 monthly chiropractor visits and me massaging the muscle spasms in the meantime...).
It is very normal for a dog to bark at noises outside - Honey hates delivery people, would happily kill the postman, and barks at any noise which doesn't belong (last one was a horse in our front garden, so you can't blame her for being a bit confused!!!). You need to train a "quiet" command to try and break the cycle (though, tbh, I haven't succeeded in this... however I can reduce the barking now....). You could also try getting her to associate the noises with a good thing - in the same way that Top Barks helped his dogs with fireworks (if you search for "fireworks and cheese" you should see a link to a you tube video showing this - it's great!!!) - so whenever the noise starts, throw some yummy treats right by her...
Try not to get frustrated by the barking, as this may reinforce it - she may feel you are frustrated at the original noise rather than her barking, so bark more to scare away the thing that is upsetting you, iyswim...
As far as other behaviour, as others have said, if would be helpful to know more - exercise, training, diet etc, as well as how you respond to the behaviour (and some specific examples, as aggression can be so difficult to interpret!) - they all have an impact on a dog's behaviour.
I think you need to get a behaviourist out to see the behaviour (whether this is the same one, or a different one depends on whether the first one actually gave you usable advice!
), but with more info we may be able to help you manage the situation while you are waiting for this...
Also, I'd be reluctant to spay her while this is still an issue - the hormonal changes following the spay (as well as the physical pain from the op itself) could cause a deterioration in her behaviour, and if it is nervous aggression, spaying has been linked with an increase in this.
